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This manual is intended for people who have never used \TeX\ before,
as well as for experienced \TeX\ hackers.
In other words,
it's supposed to be a panacea that satisfies everybody,
at the risk of satisfying nobody.
Everything you need to know about \TeX\ is explained here somewhere,
and so are a lot of things that most users don't care about.
If you are preparing a simple manuscript,
you won't need to learn much about \TeX\ at all;
on the other hand,
some things that go into the printing of technical books are inherently difficult,
and if you wish to achieve more complex effects you will want to penetrate some of \TeX's darker corners.
In order to make it possible for many types of users to read this manual effectively,
a special sign is used to designate material that is for wizards only:
When the symbol $$\vbox{\hbox{\dbend}\vskip 11pt}$$ appears at the beginning of a paragraph,
it warns of a ``^{dangerous bend}'' in the train of thought;
don't read the paragraph unless you need to.
Brave and experienced drivers at the controls of \TeX\ will gradually enter more and more of these hazardous areas,
but for most applications the details won't matter.
